NIHVIVO-336 Create StartupStatusDisplayFilter which will forcibly display the StartupStatus if there are warnings or errors.

webapp/src/edu/cornell/mannlib/vitro/webapp/filters/StartupStatusDisplayFilter.java

@@ -0,0 +1,79 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.filters;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+
+import edu.cornell.mannlib.vitro.webapp.startup.StartupStatus;
+import freemarker.cache.WebappTemplateLoader;
+import freemarker.template.Configuration;
+import freemarker.template.Template;
+import freemarker.template.TemplateException;
+
+/**
+ * No matter what URL is requested, check to see whether the StartupStatus
+ * contains errors or warnings. If it does, hijack the request to show the
+ * StartupStatus display page.
+ * 
+ * This only happens once. This filter does nothing after displaying the startup
+ * status page one time.
+ */
+public class StartupStatusDisplayFilter implements Filter {
+	private static final String TEMPLATE_PATH = "/templates/freemarker/body/admin/startupStatus-displayRaw.ftl";
+
+	private ServletContext ctx;
+	private boolean statusAlreadyDisplayed;
+
+	@Override
+	public void init(FilterConfig filterConfig) throws ServletException {
+		ctx = filterConfig.getServletContext();
+		statusAlreadyDisplayed = false;
+	}
+
+	@Override
+	public void destroy() {
+		// nothing to do.
+	}
+
+	@Override
+	public void doFilter(ServletRequest req, ServletResponse resp,
+			FilterChain chain) throws IOException, ServletException {
+		StartupStatus ss = StartupStatus.getBean(ctx);
+		if (ss.allClear() || statusAlreadyDisplayed) {
+			chain.doFilter(req, resp);
+			return;
+		}
+
+		displayStartupStatus(req, resp);
+		statusAlreadyDisplayed = true;
+	}
+
+	private void displayStartupStatus(ServletRequest req, ServletResponse resp)
+			throws IOException, ServletException {
+		Configuration cfg = new Configuration();
+		cfg.setTemplateLoader(new WebappTemplateLoader(ctx));
+		Template tpl = cfg.getTemplate(TEMPLATE_PATH);
+
+		Map<String, Object> bodyMap = new HashMap<String, Object>();
+		bodyMap.put("status", StartupStatus.getBean(ctx));
+
+		try {
+			PrintWriter out = resp.getWriter();
+			tpl.process(bodyMap, out);
+			out.flush();
+		} catch (TemplateException e) {
+			throw new ServletException("Problem with Freemarker Template", e);
+		}
+	}
+}

webapp/web/css/startupStatus.css

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+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+/* Styles for Freemarker template startupStatus-display and startupStatus-displayRaw */
+
+table.item {
+    border: thin solid black;
+    font-family: monospace;
+    width: 100%;
+}
+table.item tr.top {
+    font-size: larger;
+}
+table.item td {
+    border: thin solid black;
+}
+.error td {
+    background: #FFDDDD;
+    font-weight: bolder;
+}
+.warning td {
+    background: #FFFFDD;
+}
+.info td {
+    background: #DDFFDD;
+}
+.not_executed td {
+    color: #444444;
+}

webapp/web/templates/freemarker/body/admin/startupStatus-displayRaw.ftl

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+<#-- $This file is distributed under the terms of the license in /doc/license.txt$ -->
+
+<#-- 
+    Template for the raw page that displays the StartupStatus if there 
+    are warnings or errors.
+    
+    "raw" because this template works outside of the usual framework, in 
+    case the Freemarker context didn't initialize properly.
+-->
+
+<#macro statusItem item>
+    <#if item.level = "FATAL">
+        <#assign color = "error" >
+    <#elseif item.level = "WARNING">
+        <#assign color = "warning" >
+    <#elseif item.level = "INFO">
+        <#assign color = "info" >
+    <#elseif item.level = "NOT_EXECUTED">
+        <#assign color = "not_executed" >
+    <#else>
+        <#assign color = "" >
+    </#if>
+    <tr><td>
+        <table cellspacing="0" class="item ${color}">
+            <tr class="top">
+                <td width="20%">${item.level}</td>
+                <td>${item.shortSourceName}</td>
+            </tr>
+            <tr>
+                <td colspan="2">${item.message}</td>
+            </tr>
+            <tr>
+                <td colspan="2">${item.sourceName}</td>
+            </tr>
+            <#if item.cause??>
+                <tr>
+                    <td colspan="2">${item.cause}</td>
+                </tr>
+            </#if>
+        </table>
+    </td></tr>
+</#macro>
+
+<html>
+    <head>
+        <title>Startup Status</title>
+        <link rel="stylesheet" type="text/css" href="./css/startupStatus.css"> 
+    </head>
+
+    <body>
+    	<#if status.errorItems?has_content>
+    	    <h2>Fatal error</h2>
+    	    <p>VIVO detected a fatal error during startup.</p>
+    	    <p><a href=".">Continue</a></p>
+    	    <#list status.errorItems as item>
+              <@statusItem item=item />
+    	    </#list>
+    	</#if>
+    
+    	<#if status.warningItems?has_content>
+    	    <h2>Warning</h2>
+    	    <p>VIVO issued warnings during startup.</p>
+    	    <p><a href=".">Continue</a></p>
+    	    <#list status.warningItems as item>
+              <@statusItem item=item />
+    	    </#list>
+    	</#if>
+    
+    	<h2>Startup trace</h2>
+    	<p>The full list of startup events and messages.</p>
+    	<table cellspacing="0" class="trace">
+            <#list status.statusItems as item>
+                <@statusItem item=item />
+            </#list>
+        </table>
+    </body>
+</html>